ARM: kernel: add MIDR to per-CPU information data

The advent of big.LITTLE ARM platforms requires the kernel to be able
to identify the MIDRs of all online CPUs upon request. MIDRs are stashed
at boot time so that kernel subsystems can detect the MIDR of online CPUs
by simply retrieving per-CPU data updated by all booted CPUs.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>

2 files changed, 2 insertions, 0 deletions

diff --git a/arch/arm/include/asm/cpu.h b/arch/arm/include/asm/cpu.h
index d797223b39d5..2744f0602550 100644
--- a/arch/arm/include/asm/cpu.h
+++ b/arch/arm/include/asm/cpu.h
@@ -15,6 +15,7 @@
 
 struct cpuinfo_arm {
         struct cpu      cpu;
+        u32             cpuid;
 #ifdef CONFIG_SMP
         unsigned int    loops_per_jiffy;
 #endif
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index fbc8b2623d82..7eacd84cdc9c 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -281,6 +281,7 @@ static void __cpuinit smp_store_cpu_info(unsigned int cpuid)
         struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid);
 
         cpu_info->loops_per_jiffy = loops_per_jiffy;
+        cpu_info->cpuid = read_cpuid_id();
 
         store_cpu_topology(cpuid);
 }